5-41 Five- Day Biochemical Oxygen Demand COD Chemical Oxygen Demand of Photographic Chemicals This printing replaces the 12 73 edition COD values have been added, some BOD5 values revised, new chemicals added, and discontinued chemicals deleted The infor- mation contained in this publication has been carefully prepared and IS believed to be accurate Any particular use of such information must, however, be the respon- sibility solely of the user and must be without obligation or liability on the part of Eastman Kodak Company 0 Eastman Kodak Company 1981 Table of Contents Page No Purpose of BOD and COD Measurements . * . 3 Testing and Reliability . 3 BOD ......................... ........... 3 COD .............................. .................. 3 Sample Calculations . ............ 4- Table I BOD5 and COD Values for Individual Chemicals .......... 5 Table II BODs and COD Values for Black-and-white Film Processing Chemicals 6 Table Ill BOD5 and COD Values for Black-and-white Paper Processing Chemicals . a Table IV BOD5 and COD Values for Color Film Processing Chemicals . a KODAK Chemicals, Process C-22 . ......................... 8 KODAK Tri-Mask Chemicals . 8 KODAK Chemicals, Process E-4 . 9 KODAK Chemicals, Process E-6 . ............ 9 KODAK Chemicals, Process E-GAR . 9 EA-5 Chemicals .............................................. 9 KODAK Chemicals for Motion Picture EKTACHROME Films ...... 9 EKTACHROME Movie Chemicals . ........................ 9 ES-8 Chemicals . ................................ 10 FLEXICOLOR@Chemicals fo ............ 10 FLEXICOLORa Chemicals for Process C-41V . 10 FLEXICOLORs AR Chemicals . ................... 10 Table V BODs and COD Values for Color Paper Processing Chemicals . 10 EKTAPRINT 2 Chemicals . ................................... 10 EKTAPRINT 3 Chemicals . 10 EKTAPRINT 300 Chemicals . ... 10 EKTAPRINT R-5 Chemicals . 10 EKTAPRINT R-100 Chemicals . 10 Table VI BODSand COD Values for Processing Chemicals for KODACHROME Films. 10 KODAK Replenishers, Process K-14 . .................. 10 Table VI1 BOD5 and COD Values for Litho Plates Processing Chemicals . 11 KODAK POLYMATIC S, M, W, and L Litho Plates 11 KODAK POLYMATIC P Litho Plate . ...... 11 KODAK PMT@Litho Plates . .......................... 11 Sundries and Press Chemicals . 11 Table Vlll BOD5 and COD Values for Misce!!aneons Chemica!s . !I More Information . .................................................. 12 Eastman Kodak Company has long been committed in cleaner environment. These publications are components both words and actions to the goal of a cleaner environ- of a series known as "Information for a Cleaner Environ- ment. One small step toward this goal has been the prepa- ment from Kodak." ration of a number of publications on how the photo- The pamphlet you are reading now is part of this series graphic-processing industry can contribute toward a as well as those publications listed on page 12. 2 r Purpose of BOD and COD Measurements Genesee River approximately three miles below the indus- Used photographic-processing solutions are generally trial waste-water treatment plant operated by Eastman discharged into a municipal sewer that leads to a waste Kodak Company at Kodak Park in Rochester, New York. treatment plant. The regulatory agency may require pho- It has been determined through tests in our laboratories tographic processors and other users of the sewer to that the type of seed water used in this area is not important furnish a measure of the waste load that is to be dis- in these analyses because all had similar microorganisms, charged daily. A Weston and Stack dissolved oxygen analyzer was used For proper operation, a treatment plant must not be to measure the dissolved oxygen content, and was cali- overloaded. The total volume of waste and some measure brated using the azide modification of the Winkler method. of its strength is needed. The strength may be measured In determining the BOD of a mixture of chemicals such by the amount of oxygen that is required for the degrada- as that found in packaged processing chemicals, the mea- tion of the waste. surement can be made on the composite mixture, or alter- The most common measure of the waste load is the natively, on solutions of each individual chemical, and the Biochemical Oxygen Demand (BOD). This test provides results totaled. The latter method was chosen here to avoid an estimate of the extent to which material degrades interference (toxicity) by any of the other chemicals in the biologically during waste treatment or in a stream. Bio- mixture. Certain chemicals, when present above a "thresh- old" concentration, may inhibit the action of micro- chemical oxygen demand is dependent upon time and is usually measured over a five-day period. BOD is a mea- organisms, thus producing an erroneously low BODS. sure of the amount of oxygen required to degrade the ma- When these inhibiting chemicals are diluted below their terial. lt may be expressed as a concentration in units of "threshold" levels, as they would be in a municipal waste- milligrams per litre or as a total quantity per unit of time treatment plant, the true BOD5 of the remaining ingredients (for example, pounds per day). Since the BOD is a static can be measured. Nearly all effluents experience some test, it does not necessarily parallel what will occur in a mixing with other wastes before they are treated. When the biological treatment system. It more closely estimates what treatment plant effluent is discharged to a stream, any will happen in a receiving body of water. However, it is residual biodegradable matter would continue to be bio- widely used to estimate the load on a waste treatment degraded. plant and is probably as reliable as any other available Example: test method. Chemical Oxygen Demand (COD) is a test method that Let us assume that a photographic solution con- determines the amount of oxygen required to oxidize the tains thiosulfate, sulfite, acetate, hydroquinone, and chemicals that are measured by a particular test method. copper. (This is a hypothetical example because COD measures most of the photographic processing copper is not used in photographic-processing chemicals that are measured by BOD, and also measures solutions.) The thiosulfate, sulfite, acetate, and hy- some chemicals not measured by BOD. The COD numeri- droquinone are all biodegradable and would exhibit cal value is usually larger than the BOD. However, there is definite measurable oxygen demands when mea- no fixed correlation between the two measurements ex- sured either as a composite soiution or indepen- cept in specific cases. dently and totaled. Copper, itself, has no oxygen A waste effluent is described more completely by re- demand. However, when added to the above mix- porting both the BOD and the COD. ture, it inhibits the growth of bacteria and produces As an aid to the processor, this publication lists both the an artificially low BOD5 value. When the solution BOD5 and COD values of most chemicals that can be used passes to the drain and eventually to a treatment in the processing of Kodak photographic materials, in- plant, the effect of the copper becomes negligible cluding prepared packages of chemicals. Thus, a proces- and the BOD5 contribution of the remaining mate- sor may estimate the total waste load by tabulating the rials is the same as it would be if copper were not amounts of chemicals used and by summing the BOD5 Dresent. values individually and the COD values individually, COD: This rapid test measures that portion of the waste chemicals that is oxidized by dichromate under the test Testing and Reliability conditions. Unlike the BOD test, the COD is not affected BOD: The BOD test is made under laboratory conditions by the presence in a waste of materials that may be toxic rather than under the conditions actually prevailing in a to microorganisms. It measures oxjjgeii-demanding mate- waste treatment plant or in a stream. The dissolved-oxy- rials such as thiosulfate, sulfite, developing agents, etc. gen concentration, temperature, time, amount of sunlight, The basis for the method is the reaction of the test mate- biological population, and agitation may be different. rial with a boiling mixture of dichromate and sulfuric acids. However, the method does give a fair approximation of A catalyst is used to provide measurement of some chemi- most waste loads. The test method is described in Stan- cals not otherwise oxidized. An additional reagent is added dard Methods for tbe Examination of Water and Waste- to avoid the interference of halides. The excess dichromate Water, American Public Health Association. The precision is titrated and then the calculation is made for the oxygen of this test method, measured on a synthetic mixture in 34 demand. This test method is also described in Standard laboratories with each laboratory using its own seed water, Methods for the Examination of Water and Waste-Water, showed a standard deviation of +17 percent. The pre- American Public Health Association. cision by a single analyst was 25percent. The reliability of the test method, using glucose as the The seed water used in our tests was taken from the test chemical, is 28percent (standard deviation), 3 SAMPLE CALCULATIONS Example: If 25 gallons of a two-component solution con- FROM BODS/COD TABLES sisting of 200 grams per litre of sodium thiosulfate (penta- hydrated) and 40 grams per litre of sodium sulfite (an- The following sample calculations should help in estimat- hydrous) were discarded, how many pounds of BOD5 ing the pounds of BOD5 or COD that might be discarded would be sent to the sewer system? into the sewer through the discharge of photographic Because this solution has more than one component, waste effluents. the pounds of BOD5 must be determined for each compo- The examples are given for BODS values. The same nent and added together to find the total of BOD5 going calculations can be applied for COD values. to the sewer. First, for sodium thiosulfate (pentahydrated), A. From Prepared Solutions 25 gallons When BOD5 gallon of solution is known directly from per 0.20 pound of BOD5 per pound of chemical table.